Thursday, 3 February 2011

Muscle Memory - it's all in the mind!

Muscle memory is a common phrase associated with the martial arts as well as in other sports, playing a musical instrument, riding a bike or in the acquisition of any other psycho-motor skill for that matter. It is a useful way of trying to understand what is going on: through repetition of a set of muscular actions, that muscle (or group of muscles) will eventually react to a stimulus in a predictable and reliable way. It is as if those muscles have ‘remembered’ what to do and the movements become automatic without the need for conscious control.

Unfortunately the phrase ‘muscle memory’ grates on me a little! It may feel as if your muscles just know what to do all by themselves and you aren’t consciously sending them messages to contract or relax at a given moment but your unconscious brain is working very hard to tell your muscles what to do in any given situation. Clearly memory resides in the brain not the muscles. In my opinion a more accurate phrase to describe what is happening is motor memory.

We control all muscular movements in our bodies through the motor system which basically consists of the brain, neurons (and their synapses) and the somatic muscles. If you want to move a part of your body, your brain sends the signal down the appropriate neurons to the appropriate muscle(s) and the muscle contracts to move the required limb. Repetitive patterns of movement, such as walking or cycling, eventually become unconscious actions, though they are still being continuously controlled by the brain.

When we are learning a new skill, say for instance a new kata or a new type of kick, your movements may be clumsy and jerky – not at all like your instructors movements. This is because your brain has not yet laid down a memory pattern for this movement. It hasn’t recruited the appropriate motor units in the muscle and developed new neuronal and synaptic connections that enhance communication between the muscle and the brain.

With repetitive training of the required skill, the necessary motor units in the muscles are recruited, neurons and synapses are created to control these motor units and a ‘memory map’ becomes laid down in the brain which enables the required movement to be evoked quickly and accurately when a stimulus is received. For example, you see a punch coming towards your head (stimulus) and before you know it you have evaded and blocked it. You didn’t think about it, it just seemed to happen automatically! Well it probably did happen automatically because it’s a technique you’ve practiced over and over again, your brain just executed the move below your conscious control – but rest assured it was still your brain controlling it.

As a new ‘memory map’ is developed in the brain your execution of a particular technique, let’s say that new kata or kick, becomes more fluid and natural, more precise and predictable. This is because your brain has better, more precise control of the necessary muscles needed to carry out that movement.

So, how do we create these ‘memory maps’ in our brains (motor memory)?
There are three phases to motor learning, i.e. learning a new skill.

Cognitive phase: learning a skill for the first time requires a great deal of thinking. You have to be consciously aware of every single movement you have to perform. Think how mentally taxing learning a new kata is. Not only do you have to learn and remember the sequence of steps, you have to think about coordinating hand and foot positions, which way to look, which leg to place your weight on, which direction to turn…. there’s just so much to think about. During this phase you go through a process of trial and error to determine which strategies help make the movement work better. Initial progress can be quite quick.

Associative phase: You’ve worked out the best way to do the actions, so during this phase you fine tune adjustments to make the performance better. Improvements are more gradual and this phase may take a long time, still requiring a lot of conscious effort. We often perceive this as a long plateau phase in our training.

Autonomous phase: This the phase where the ‘memory map’ is complete and the actions become automatic and unconscious. It can take months or years of training to achieve this. This is why martial arts take such a long time to get good at.

During the first two phases a process of memory encoding is taking place. New neurons are being created and motor units in the muscles recruited. These new neurons are fragile and susceptible to damage. This is why we tend to keep forgetting steps and movements we are learning and need reminding a lot when we first start. Several areas of the brain are active during this phase. During the final phase the process of memory consolidation occurs. This is much more stable and less likely to degrade. Long term structural modifications are made to the motor map which prevents degradation. This is why once we have learned a skill well we tend not to forget it even if we don’t practice it for years, for example, riding a bike.

How can we enhance motor learning and motor memory?

Feedback: there are two types of feedback occurring during learning:

Inherent feedback: you constantly give yourself positive and negative feedback about your performance and make corrections. For example, you notice that you lean forward to hit the pad so you correct this by stepping forward a little. You learn to correct a wobble when you turn by placing your feet further apart. We can enhance our use of inherent feedback by having a clear picture of what we are aiming for so that we can compare our performance to an ideal one. Inherent feedback is a very active process – you have to think critically about what you are doing. Videotaping can be a good way of helping us to improve our inherent feedback.

Augmented feedback: this is when someone else gives you feedback about your performance. Our instructors regularly critique and correct our performance. This is good – it speeds up our learning, listen!

Endurance and Strength training: Endurance training helps to protect the newly forming neurons that make up the developing memory map in the brain by up-regulating the production of neurotropic factors which prevent the degradation of the delicate new cells. The effects of strength training are seen in the development of new neurons in the spinal cord well before there are any noticeable changes in the muscles being exercised. This suggests that endurance, strength and skills training are synergistic; enhancing the rate of motor memory encoding and consolidation.

Visualisation: just visualising yourself doing the techniques you are learning has been shown to help induce new neuronal activity that enhances your real performance of the skill. Day dreaming isn’t a waste of time if it is focussed on learning those skills you want to perfect!

However you like to think about it, muscle memory or motor memory, it’s all in the brain! If you think about skills learning as something that is happening in your brain rather than your muscles then you can focus on things that enhance the process such as visualisation and inherent feedback. Of course though, your skill level is going to be limited if your muscles aren’t in good condition so some endurance and strength training are also important, particularly as they have a synergistic effect on producing those all important motor memory maps in your brain!

Well done Sue. And it's encouraging to see the other comments which support your post. This is what the martial arts needs (in my opinion). It is frustrating that 'golf' is more advanced in training methods and fundamental use of more advances in the sciences than the martial arts. I'm advocating (and researching) the use of technology (video) to improve training martial arts tactics and techniques (via immediate feedback and reinforcement). I don't know if it's presumptious to welcome you to my world. BTW, Attilio Sacripanti has developed a post-graduate/masters degree for judo. A kindred spirit in looking to the advances in science to improve our understanding and study of the tactics and techniques of the martial arts. A warning though - since virtually nobody looks to science, there is a lot to apply and it can become a black hole (which is where I currently reside).

John, I'm happy to be in your world. I'm all for the 'appliance of science' in martial arts. In fact shukokai karate was developed from shito ryu karate following careful analysis of biomechanical principles so it is well known for being one of the faster, hard hitting styles.

I agree with you about the use of video tape to train. It is an excellent tool to learn from, be it learning to improve your shortcomings or by seeing what a technique/stance/movement should look like (by seeing others on film).

All the concepts of motor learning you are also relevant to physical rehabilitation after neurological injury and or disease. The concept here is intensive active exercise practice to get back the function that has been lost. See products like the HandTutor system for upper extremity rehabilitation following stroke or spinal cord injury or an example.

Felicia, we don't actually use video taping in our club at the moment which is a shame because I really think it would be useful. I may try filming myself at home though. I think that sometimes you just can't quite see what someone is trying to get at until you see it yourself!

MediTouch, Years ago I used to care for stroke patients when I was working as a nurse. The kind of equipment that you discuss on your blog just wasn't available then (well not on the NHS.) It's great to see so much R&D being done now to aid in recovery of function following strokes and other neurological problems.

You got into a lot of detail about muscle memory! The way I've always thought about it is when learning endless techniques - one does not strive to retain every detail (in a fight for instance) but rather the ways ones body can react.

I have always let my body to put together the moves as it sees the openings.

Hi John, you say "...let my body put together the moves as it sees the openings". This seemingly automatic response is what we are all striving to achieve but my point is that it is your brain that 'sees' the openings and your brain that 'puts together the moves'- it's just all happening below your level of consciousness and doesn't require any cognitive thought. Of course you don't need to know how the process is happening in your brain to be able to do it, like for you, it will just happen with hard, repetitive training.

Great Post Sue. New to this Blog thanks for giving me the heads up about it. Am enjoying the Blog so far. Really like that post. I have to agree with the term "motor memory". Like that better than "muscle memory".

Top post, Sue. What complicates this is the different ways in which people learn. Most are visual, they see it done properly, they follow. Some are audio-oriented, you explain it, they follow. Some are touch-oriented, you move their arm or leg for them, they follow. I have yet to meet anyone who is smell-oriented, but have had a few kids "clear the floor". lol

Hi Matt, You're right - learning is very complicated and we are definitely not all the same. I did an on-line test a while back to see what kind of learner I was (I thought I was a kinaesthetic learner) but I turned out to be a predominately visual learner. I scored virtually nil on auditory learning - just shows I never listen! LOL